Sunday, July 31, 2011

I've been at a workshop on theoretical aspects of cosmology for the last two weeks. It's called the PITP and is extremely interesting! It's held every year at the Institute for Advanced Study, which is an independent research institute close to Princeton in New Jersey.

In our information packet, there was a page-long warning about Lyme disease, which can be caught from ticks in the wilds of the campus. Deadly invisible animals everywhere - soon I'll get homesick! On the first day, everyone kept close to the path just in case they were attacked by giant marauding arachnids.

About 24 hours after we arrived a shuttle was arranged to drive us to the nearest supermarket - only 20km away! Princeton is anything but a bustling metropolis, if you get my drift. Entering 'shoprite' or something I had to negotiate 20 or so shelves stuffed with cookies, followed by an aisle of cakes in plastic containers covered in heaps of icing, followed by yet more cookies! After traipsing all over the store collecting non-poison, I staggered back onto the shuttle carrying 6 bright yellow bags of groceries. Hopefully enough to feed me for seven days!

During the check-in process, we were given a box of afternoon tea refreshments, the centrepiece of which was a rather exciting looking sandwich. If you will permit a short excursion into the fascinating area of US farm subsidies; a push for healthier milk led to the popularisation of skim milk products. So far so good. But the diary industry was left with an excess of cream. There is really nothing sensible to do with cream except to eat it. So the diary lobby (yes! It exists!) has pushed for wider consumption/subsidisation of cheese and butter. Which kinda defeats the purpose of skim milk in the first place.

This sad fact impinged upon my life thusly - the upper part of the sandwich bread was encrusted with a delectable layer of melted cheese. Don't get me wrong, I actually rather like cheese, but have been rather allergic to milk products for the last two years or so. The sandwich upper was lain aside. Beneath two slices of the rather less appetising orange american cheese shone sunnily forth. They too were consigned to the purgatory of the adjacent fold of grease proof paper. I was suspicious that the sandwich may be built upon a foundation of milky creamy stuff, but it passed the sniff test. I proceeded with abandon. It was scrumptious. Perhaps a little too scrumptious. Forensic analysis of the crumbs revealed, to my utter horror, that the bottom of the sandwich too had a stealth encrustation of baked cheese.

Having not eaten this much of the forbidden fruit in many months, I was now curious (like the scientist I am) to see what would happen. I am pleased to report that a repeat of the precipitous weight loss that marked the last half of 2009 did not repeat itself. However the usual milder response of fatigue and irresistible drowsiness while seated has recurred. Sitting in 5 hours of lectures a day in front of the creme de la creme of theoretical physics was daunting enough. Spending most of that time in bizarre, cheese-filled dreams, was slightly embarrassing. Fortunately at this sort of event jet-lag and workaholism is not so uncommon that sleeping all day is particularly out of the ordinary. Still, when I'm able to control my diet better I will have to return to the webcasts (as yet only fabled) and see what I missed out on. Moving to the back of the theatre and less comfortable seats helped to an extent!

For the record, all the speakers here are highly regarded researchers in their fields, including Susskind, one of the inventors of string theory. Ed Witten (the only physicist to ever win a Fields Medal) is not officially part of the program, but has joined many of the sessions. It is slightly intimidating to be amongst people who would eat my hardest research problem for breakfast. So I have to keep it a secret! As my research is tangential, I do not know most of their work except by reputation, which is also slightly awkward. E.g. "Hi, I'm Casey. I hear you do good work, but I have no idea what it is..."

On Thursday afternoon I walked through the town, visiting the record store, a small park with a list of regulations and rules about 8 feet high, and saw many of the famous buildings in Princeton, including the stairs that Russell Crowe dropped books down in the movie 'A Beautiful Mind', about the economist and Nobel Prize winner John Nash. The next day at lunch the REAL John Nash was sitting at the next table! With a few Nobel Laureates at the cafeteria I could almost be back home at Caltech!

Also worth mentioning is the exterior shots of the "Princeton-Plainsboro Teaching Hospital" in the television series "House" is actually the Frist Student Center on the Princeton Campus. Like everything else, however, it's actually filmed and produced in LA.

On Friday afternoon we were finally released from the rather strict schedule we had been following (wearing a name tag at all times is compulsory!) and, throwing a spare shirt or two into my capacious laptop bag, I sprinted for the train. Except that the ambient temperature was about 40C, so my sprint was more of a purposeful melt. If it had been much hotter, I could have exploited the Ladenfrost effect and scooted there on a frictionless layer of steam. Would have simplified the calculations too!

To the train! Before long I was once more in New York's Penn Station, which have all the charm of a subterranean Burger King drive-thru, but a worse smell. In particular, access to the platform from the concourse is via a stairway too narrow for two (normal sized) people to pass, and platform numbers are not announced until 10 minutes before departure. In contrast, for instance, every railway station I visited in Russia was designed and built exquisitely to corral large volumes of human and freight traffic in all weathers and temperatures with maximum efficiency. I am aware that Penn Station was originally a full scale replica of the Baths of Caracalla, with rolling stock instead of a hypocaust, but its loss is an indelible stain on the architectural legacy of the entire United States.

I had received word (via the customary homing pigeon) that my CS host for this weekend K was running late, so rather than brave the metro tunnels I emerged in the sunlight. Elementary arithmetic soon had me zigzagging south east towards my destination. I arrived in time to buy some cool drinks and hang my new hammock (ordered and delivered to Princeton by Amazon Prime!) on the roof before I was joined by K and another CSer, H! Sadly most of the view is blocked by the rampart when sitting in the hammock, but the sunset and sky was, if anything, in bolder relief.

Returning to the blessed cool of air conditioned comfort below we ransacked the fridge and produced a very passable pasta sauce. There is nothing quite like a variation on a theme!

Over the next few days H and I saw Captain America (from the front row) which very, very nearly exceeded my extremely low expectations, but was otherwise fun. We purchased some cupcakes from Sugar Sweet Sunshine only to be served by someone from Sydney! Graduated from Strathfield in 2005, the same year I did! I sometimes try and imagine the tangle of lines embedded in 3+1 spacetime by the movement of people from place to place, and how they diverge and clash again. It was still extremely hot, even with the AC on, except about below the knees. On Saturday evening we held a party on the roof, to which about a dozen brave souls turned up. The weather held, the hammock bindings held, the alcohol supply held. Even K only triggered the emergency alarm once!

Outside the cinema H and I had been bailed up by a journalist who wanted to ask us our opinion of the recently reported death of Amy Winehouse. Aside from the usual questions, one in particular stuck in my mind. "Do you know anyone with whom you would want to intercede?" At the time I answered that I thought doing so would probably only heighten a feeling of condemnation and isolation, as it apparently had with Amy. I'm still inclined to think that to assume I (or anyone) could 'save' someone from themselves is at best naive and at worst condescending. In my opinion the gifts and privileges I've received, through no fault of my own, are much too valuable to risk on what I see as rather juvenile chemical attempts at escapism. That, and I prefer my experiences undercooked. I've travelled far and wide, however, and I'm aware that my feelings and rather hard line in this matter are certainly a minority, and possibly unique. It's not that I'm overly cautious or averse to danger. Just stupid, pointless danger!

Later on Sunday I met K one last time at Bryant park and we had Thai noodles for dinner at a nice place near 36th and 8th (I think??). After exchanging the requisite keys I bolted for the station, and once again immersed myself in the company of peculiar people. Nearly everyone had an iPhone, including me. Though mine is increasingly unusable due to a large crack in the LCD and fluid leakage. The exterior of the phone remains pristine after nearly 2 years of ownership, so I'm a bit cheesed off about the whole thing. Planning an upgrade to probably a Samsung+Android combo in October so I can run some UNIX shell and ssh directly into the machines I use at work. Then I can make Linux move files with a frustrating keyboard and terrible user interface from the comfort of some lecture theatre I would otherwise be sleeping in!

Back at the IAS, the weather had turned. On Monday it rained heavily for most of the afternoon. A few of the nuttier theorists from Stanford expressed a desire to play soccer that evening regardless, however at 7:30 it was only D and I on the pitch, so we threw a Frisbee at each other for a while. In a cooperative sense. After that I was still a bit bouncy, so sandals in hand I took off down Einstein drive towards Bloomberg hall. Through the pouring rain, I splashed in cool puddles down to warm tarmac, pattered over the slick-looking slate, and flew down towards the pond. I paused for a second to catch my breath, and on an impulse pulled my damp teeshirt over my head, rolled it up, and stuffed it down the back of my pants. With a single look over my shoulder to check for oncoming traffic I flickered off on presto footsteps down a path I'd discovered the previous week. A rough dirt trail, it wound between the (rather undergrown) trees of the Princeton forest towards the (little) canal. In the evening's fading light and steady rain I could see moss, grass, dirt, stones, and muddy rivulets, slick underfoot. With short footsteps an unexpected stone is a minor inconvenience, and before long I had reached the water, spanned by a precarious looking wire and wood suspension bridge. I stood in the middle, sandals in hand, watching the rain smash down into the water where I had seen a crane the previous week. Then, lest the setting sun catch me out, I turned for home and zoomed back up the trail. Before long I was back at the pond, and stopped at the ice warning sign. In front of me was the main hall of the IAS. To the right, half a dozen deer looked up, surprised to see me. To the left was the pond, the surface mostly rough and choppy from the rain. Beyond, the sun shone up from the horizon beyond the clouds, casting the underside in that rare yellow glow you see combined with a rainbow about twice a year if you're lucky. I lapped the pond once and ran back via the soccer pitch under scattered yellow light and falling raindrops. Back home, I waited for my hair to dry and tried not to forget. I ran about 2.2 miles (3.6km), which is nearly twice as far as I've run since maybe 2003, and easily the furthest I've ever run without any shoes. It's easy to forget the texture of the ground and what it tells you about where you're going!

I made Pad Thai for dinner, and followed it up on Tuesday with a Moroccan chicken and vegetable stew, which was well received by my housemates, despite a few technical errors in the execution. Next day I experienced sleep paralysis during a lecture, which was slightly disconcerting! Later at lunch I joined an audience of awed grad students and post-docs watching an exchange between Witten and Arkani-Hamed concerning, inter alia, the possibility of the LHC discovering two Higgs bosons before next summer, thus simultaneously disproving both natural and fine-tuned models. For physicists, this is about as good as witty repartee and edgy humour gets. Arkani-Hamed, who is also faculty at the IAS, was doing most of the talking. Clearly, he was nearly as awed as the rest of us! My efforts through the last week to think of something sufficiently intelligent to say to Witten finally paid off! I asked if he'd care to take a side on the toroidal event horizon existence problem currently being bandied about by the grads back at TAPIR.

INTENSE NERDINESS (muggles may wish to skip to the end): This is the problem. A black hole is a lump of matter dense enough to trap light. This is a thing called 'escape velocity', which, like most physics things, means exactly what it says. Nothing can go faster than light (which is why we will eventually use nothing to power space ships <--- physics joke), so if light can't escape, nothing can. The stationary, uncharged, non-rotating black hole was the first solution to the Einstein Field equations. Sadly, that won't earn you a PhD anymore. Rotating black holes are similar, but a bit oblate. They too are stable with respect to time, so determining where the 'event horizon', or the surface beyond which light cannot escape, is relatively straight forward.

At Caltech, we're solving (inter alia) the problem of a general black hole binary inspiral, merger, and ringdown. Here's an oldish video of two non-rotating black holes merging: http://www.youtube.com/watch?v=R9HTdpQMAjY. If the black holes are spinning, then the merger process involves an 'elephant trunk' of event horizon emerging from each black hole across space and eventually connecting to its opposite number. Note that at all times the event horizons of the holes are topologically equivalent (continuously deformable) to a sphere. However, it has been an open question for nearly 20 years whether this process can lead to slightly more exotic topologies. In particular, it is theoretically possible that each elephant trunk could connect somewhere half way up rather than at the ends, leading to the (momentary) creation of a torus, or doughnut topology. Topology just means 'shape'. Note that a typical coffee mug is also topologically equivalent to a doughnut. The discovery of toroidal event horizons would thus complete the holy physics trinity of coffee, donuts, and intense nerdiness.

Technical problems include solving the problem with adequate resolution (on top of which we're just getting). Additionally, finding the event horizon requires an evolution backwards in time from the final, time-stable state to discover which light rays only just escaped to infinity. Infinity is where escaped light rays go. Lastly, not all observers would see the same thing. The event horizon is a 2D surface in 3D space, so in 4D spacetime, the event horizon is actually a 3D manifold that separates two regions of space (an inside and an outside). Then what an observer sees is actually the surface of their past light-cone. Even if a whole bunch of observers get together and agree on a global time (like we do on the surface of the earth), this is non-unique. It's called a foliation, or slicing of space time into space-like surfaces separated by small, perpendicular time intervals. In particular, travelling at different speeds leads to different natural foliations. In order to infer the existence of a toroidal event horizon, the network of observers would all have to be travelling at some particular velocity. Noone is quite sure what this velocity might be. There is a good chance we'll have a relatively good answer by 2015, marking the 100th anniversary of the publication of General Relativity by Einstein in it's final, correct (so far as we can tell) form.

END INTENSE NERDINESS: So, an interesting problem. Naturally, Witten stated that it was not his area of expertise and declined to offer an opinion. My feeling is that toroidal event horizons almost certainly do not exist in nature, though I think they are theoretically possible and could be simulated on a computer. There's a diagram in the album somewhere.

That afternoon I attempted to prove the Jacobi identity for spin-0 4 particle interactions using spinor-helicity formalism (with limited success), then walked to the IAS director's house for pizza and pool party. Although no-one remembered that me and another guy were lactose unfriendly, someone else who didn't turn up was, so all was not lost. I hadn't had a swim in a pool since last August (nearly a year ago), and that was just a small pool in a banya in Magadan. Mostly guys, so there was a lot of water-frisbee-polo, splashing, a relay race, swimming under water, and I did a few flips into the pool to assess how much parkour in Orlando had rubbed off on me. Conclusion - don't try a forward somersault on concrete yet. The water was warm and it was a rather lovely evening. Plenty of fun was had by all! Worth mentioning is that the pool was installed by the former director Oppenheimer (probably not personally), who was one of the driving forces behind the Manhattan project, which led to the creation of the atomic bomb. I suppose he needed somewhere to keep his souveniers!

Around sunset I leapt out of the pool like a whale on speed and, scooping up my stuff, ran past a few slightly confused fellow attendees right back down the road to the house. Putting on my shoes would have slowed me down too much! Back at the diggings I listened to "The Book of Mormon" (the broadway show, not the book), prodded couchsurfing for a place to stay on Saturday (success at last!) and got ready for bed.

The rest of the program rushed to a conclusion. On Friday during lunch, Ed Witten was once again called upon for his expert opinion, this time on the 'tau-pi' religious divide. In recent years there has been a push from certain obscure corners of the academic community to use an alternate notation for units of angle in radians, tau. Numerically, tau = 2*pi, where pi = 3.14159... The reasoning for this is best told here: http://tauday.com/. Ed said something along the lines of "it's a bit late now", which I think applies pretty well for people who make a living out of mathematics - they battled past their confusion long ago!

At length I packed my bag, returned my key, posted my leftovers to K and A in NY, walked into town, bought some merchandise, and swung past the exterior set of the Princeton-Plainsboro teaching hospital (from the TV show "House") for good measure (The Frist Campus Center) on my way to the Princeton train station. Before long the density of nerds had dropped to its stable background level, and the wonders of Jersey Transit sped me away, back to real life.

Monday, July 18, 2011

My shuttle to the airport was due at 6pm. But first I had a friend over to borrow some music. I was reading the foreword to the new book "The Quotable Hitchens" by Martin Amis. Next on the list was returning to "How to Survive in a War Zone", which had exactly the same shade of red for a cover. My friend and I swapped observations on whether private cars or taxis were more affordable. I almost never even take a taxi if I can help it... but then I've never actually visited a war zone, aside from the interior of my room. As my friend helpfully pointed out.

Then my parents skyped me for the 5 minutes my internet managed to work, I grabbed my bag (everything in my laptop bag again; the less you take, the quicker it is to pack!), and headed for the exit. On the street I found the shuttle, which was also waiting for another Caltech person. His name sounded familiar, and it was N, who was on the Mt Whitney climb! He arrived in the nick of time (for a conference in Boston or something), and together with an expert in magnetism, we set out on the nerdiest drive to the airport I have ever had. We discussed zeolites, rare-earths, hydrogen storage, and the ever-increasing uses of superconductivity for magnets, including large windmills.

I had taken an early ride to avoid traffic jams associated with 'carmageddon', or the complete closure of the 405 for the weekend. In the end we made good time, and soon enough I was opting out of the security scan, starting a trend, and asking the TSA personnel pointed questions about their own radiation safety. After I received the definite highlight of my week (up to that point, at least!) I put all my stuff back in my pockets, ate dinner, navigated the interior of terminal 6 (I think) STILL being renovated (since at least last November), boarded the plane, and located my seat. Fortunately I was not seated next to an overweight person, but somehow Spirit managed to recreate the experience (and after being forced to shell out about another $160 to check in and bring a bag, even when done over the internet!). Both the aeroplane and the seats were ancient and worn, and after a beautiful climb out of LA over the lights (it looks better in the dark), I folded myself up into a shape resembling the Chinese character for 'intestines', I attempted to snatch a few hours of sleep. Pretty soon we caught up with the dawn at Detroit. Because we were in a plane, we could see it while the city lights were still on down below.

After a short break in Detroit (which has a charming airport terminal, at least in comparison to LA), I boarded a short flight to NY La Guardia. Having paid $10 to print my boarding pass (at home) I had a terrific window seat view of Manhattan on approach. The plane ground to a halt metres from the wet, splashy end of the runway, and soon I was on a bus through Astoria (home of the American Steinway factory) and Harlem to Columbia University. One short subway ride later and... oh bugger. Someone was murdered where I want to get off, and now the police are holding things up. Soon enough I popped into a grocery store and bought a loaf of bread for breakfast, then met my couchsurfer. Normally one meets couchsurfers in an at least semi-public place, but here I knocked on their door. "A, I'm Casey", "Come in, come in!" I ditched my luggage, unpacked, and chatted for a while. A had misplaced her phone, so we had to organise 'old school'. I actually prefer that. We headed downtown, ate some oatmeal-dark chocolate biscuits for lunch (travel = bad diet!), and caught Harry Potter 7.2 (in 3D!). "HARRY!!!!!!" I screamed a few times during interminable pre-show advertisements. And later, during the climactic show down between good and evil, with a decent quantity of teen hormones thrown into the mix. I compulsively cheer whenever people on screen kiss. Ever since I started watching "Bones", where it took about 7 seasons to get around to it...

After the movie we headed further down town to High Line Park, a recently built park on a disused section of train line above the traffic. It was quite crowded and rather nice! A departed to 'do work' or something equally unlikely for a fellow grad student. I headed up to 42 and Broadway to check out Times Square and the theatres. I was seconds away from buying a frightfully expensive ticket to see D-Rads in "How to succeed in business without really trying" or whatever it is when I got a text message from A. A different A. I think we're up to three. This was the A I couchsurfed with in April 2010, just after the Caltech prospective grad student open day. K (the other CSer from last year) was having a roof top party on the Lower East Side, and I should totally come. So I did (catching a bite to eat on the way). I arrived before A, before K, indeed, before everyone. So in due course I helped carry stuff up on the roof, ate some food, and caught up on 16 months of news! It was, I think, the first time I've ever seen a CSer again, and it was nowhere near as bittersweet as I thought it might be. Ordinarily, the fuse of friendship burns bright and fast with couchsurfers, since there is an implicit time limit. In this case, at least, there was at least a little bit more to go. The city formed a wonderful backdrop to party as the sun set over New Jersey.

At 10:30, my spidey sense told me that I should leave to avoid inconveniencing my host on the other side of the magical island. I got lost only once on the subway, and was soon standing beneath the first shower with good pressure I've been in this year (at least), which prefigured a delightful 10 hours of sleep (making up for the one hour the previous night) on a very comfy couch.

Next morning I woke, folded the sheets, checked email, and had a single slice of bread for breakfast. I stopped by at the cathedral of St John the Divine in case they might be playing the amazing pipe organ (on which the story linked to at the top is based), but no such luck. I swung past central park on my way to Penn Station, where after the requisite period of wandering around deciphering signs, bought a ticket and caught the appropriate train with whole minutes to spare. Two thoughts struck me as the crowd belched down the stairs onto the platform. First, why did they add escalators that destroyed the stairs (making them too narrow for people to pass). Russia could teach them a thing or two about station design. Second, I hadn't eaten lunch. Travel is like that.

Atop 800 tonnes of American engineering, I zoomed south down the BAMA to Princeton Junction, where the passers-by became conspicuously more nerdy. I have a nerd-radar. Soon I had boarded Princeton's little 'dinky' train to the main campus, and began walking with a couple of other guys towards the Institute for Advanced Study. They were somewhat perplexed by my light packing. My hobby: sow discord and confusion with my travel habits.

Soon I was registered and had retrieved a lunch with an intact cookie and an iced tea. I don't think I've ever had iced tea before. It's basically pure sugar. I was so sad! The beef sandwich bread had melted cheese on top, so I sacrificed the top piece of bread. Underneath was more cheese (the weird orange american sort), so that too got the flick. After finishing the first half, I realised the bottom half too was cheese melted. I mean, I understand that with skim milk there's a huge abundance of cream to be processed and eaten, but REALLY, people? I was losing enough weight just from forgetting to eat for a few days here and there, and now I've been cheesed. Worse, I've been crypto-cheesed!

The accommodation is on the comfortable side - certainly nicer than the Catalina apartments, and I look forward to settling in here a bit over the next two weeks, with a possible weekend jaunt back to NY. I imagine the rest of the workshop will be rather less interesting for non theoretical physicists, but we did get one last adventure. My housemates (A and S) and I went into town for dinner and a few supplies to last us until the shopping trip tomorrow. The dinner was the definition of unremarkable, but we took a shortcut across the golf course on the way back. While there was some risk of being bitten by a tick or something, we saw about a dozen fireflies, which was pretty awesome.

If every day could be filled with as much interest and joy as the past two have, I would be a very happy man indeed!

Tuesday, July 12, 2011

It started with an innocuous enough email; spare ticket available, any takers?

Four days later, I was zooming east to Orlando (via Charlotte). D, the man sitting between me and the window, was an environmental scientist from Houston. We had a quick chat about speculative physics and at the airport, his father and friend gave me a lift to my hotel, the retro-chic Days Inn.

Sitting in the lobby some time later between naps, who should I run into but J, a guy who graduated from my high school a few years ahead of me, and who I hadn't seen in 8 (?) years. Here for the same reason, of course. What reason? (I hear you cry.)

I took a few naps, answered some emails, and ate dinner at a local Indian place, which was satisfying. I ordered extra naan to fold up and stuff it in my pocket. At 1am we got in the car and drove to the bus meeting place, met the rest of our six person group, and jumped on the bus. The next 10 hours consisted mainly of waiting in over air-conditioned buses or rooms, intraffic jams and security procedures. I'm not sure what security was looking for, but it wasn't particularly thorough. We also spent 2 hours at the Kennedy Space Center before 5am, checking out the exhibits. Most were quite good, but some were hilariously outdated. Eventually us and 8000 other people were funneled out into the car park, put back on buses, and delivered to the east causeway by about 9am. We found a place with good visibility and borrowed some chairsfrom under a marquee, and settled in. I munched my pre-stowed naan, folded my arms and legs in the traditional manner, and duly passed out.

By about 11am the countdown (did I give it away?) was proceeding apace, weather trouble had abated, and the feed provided an interesting insight into the processes of putting the astronauts inside, taking spare stuff out, sealing the hatch, leak checking, retracting gantries, and so on. I pulled out my binoculars and got the focus just right. At 9 minutes, the last hold went through, prompting cheers from the people lining the shore. At 31 seconds, control passes to the orbiter's computer, which began oxygen flow. The countdown paused! A sensor on the ground had failed, and the gantry might not have retracted adequately. Camera 61 swung into position and confirmed that it was indeed retracted, the countdown resumed (within a 10 minute launch window!), and shortly afterwards the shuttle was obscured completely by billowing clouds of hot, poisonous gases. As the peak of the shuttle emerged from the cloud a deep rumble reached our minds and bodies, and the shuttle continued upwards on blindingly bright pillars of gas. For about 40 seconds it remained in view below the clouds as the loud speaker updated us on its consumption of fuel and steadily increasing speed and altitude. At half a ton of fuel per second, it's not really a hybrid. A minute later it was seen between a gap in the clouds for a few more seconds. 10 minutes later it was in orbit. A video can be found here: http://www.youtube.com/watch?v=lSY4Z_nso5U;

Rather astounding, and definitely worth the last minute hassle of organizing it! The shuttle was inefficient, expensive, and did not fulfill its mission criteria. But the shuttle was a flagship project; a signal of wealth and prestige. Certainly lessons have been learnt, and I await the maturation of the SpaceX developed Falcon rockets. Already they've launched a seven person capsule into a stable orbit with functional life support. To me this is astounding. A private company has achieved in a few years what most space-faring nations have still not demonstrated.

Back to the hotel by 3pm, a well earned shower, and sat in the lobby using wifi, but MSNBC nonstop news, featuring pointless analysis of the Casey Anthony acquittal blared right into my brain.

That evening we stacked the apartment. At some point D rolled over in his sleep and grabbed my ear; a very strange way to wake up during the night. Of course after that I had some bizarre lucid dreams featuring harpies, unsafe auditoriums, and steampunk styled caverns in whichgravity was optional. The following day wifi was much more usable, as the TV in the lobby had apparently broken. There were two more days in Orlando, and only 1000 pages of quantum and stat mech/thermo to revise for Tuesday's qualifying exam. If I pass it, it'll be the last exam Iever do which counts for anything. :) Possibly...

Next day I had a slow start, plenty of revision, ate some snacks, and read a lot of physics. At about 5pm I got in touch with a local CSer, A, and he took me on a tour of the nicer parts of Orlando, after which my attitude to the place softened considerably. After chatting abouthis Obama mannequin, testing the trampoline, and sharing insane travel stories, he dropped me at his blue-haired housemate's parkour gym. I walked into the un-airconditioned warmth and felt the sprung floor beneath me. About 20 guys aged between 10 and 30 were bouncing allover the place. I signed over the rights to my undamaged organs and joined a queue of 'beginners' doing forward somersaults from a trampoline onto a mat. I watched it a few times, figured out the essential elements, and soon enough was pulling flips with the best of them. I even didn't land on my head most of the time! As I tumbled in free fall I noticed a hole in the wall right next to me...

Meanwhile a few other guys were learning tricks of various kinds, jumping over obstacles, doing forward, back, and sideways flips, jumping off the roof and rolling, and (very rarely), fallingspectacularly. A kid who looked about 12 sat at the side with his arm in a sling, and offered to teach me 'anything'. Apparently he was an instructor within the group, along with about half a dozen others. I had never seen these sorts of antics before in person, and the agility impressed me. Here's a video of similar stuff: http://www.youtube.com/watch?v=1fouvwilGWc, the free-running scene from a recent James Bond film: http://www.youtube.com/watch?v=jJubOZLpp4A. The video I shot: http://www.youtube.com/watch?v=RXGq8L333kQ

I jumped a few obstacles, fell a few times, and judged when I'd exhausted my luck's ability to hold out. As I left, I noticed that the mothers of the boys in the class sitting in the air-conditioned foyer, ostensibly keeping an eye on their children and discussing how best to interest them in school work. I'm pretty sure they were there for the shirtless and obscenely well-muscled gymnasts doing their thing, though. Eventually A returned with P, and we headed for dinner. Sadly all the pho joints had closed and we had to settle for hotpot, confusing the restaurant's wait staff no end, since not one of us was Chinese! After dinner we walked into town, checked out the rather noisy clubs, walked a few blocks on the railway tracks (balancing, of course, to the bemusement of some mounted police in the area), and eventually I cabbed back to the hotel.

Orlando is a rather spread-out city, but not every attraction is hugely expensive. There is, forexample, a section of 1970s era parks which often have a single attraction, such as one water slide, or put put golf with live alligators. Apparently there's also a restaurant run by a middle aged Chinese woman with peroxide blond hair, who has a cable channel pushing the philosophy that world peace will come about when all people, AND animals on earth convert to veganism. The videos also feature simultaneous subtitling in 30 languages, which is apparently quite something.

I had noticed very few mosquitoes throughout the trip, even when on the causeway. Apparently the local government sprays a LOT of some relatively un-carcinogenic chemical to keep them at bay. Some other local oddities include sinkholes, which open up at random in response to depletion of the local aquifer in the otherwise flooded limestone of Florida. Main methods of remediation include conversion to a lake (neaten up the edges) or filling with concrete. D and I agreed that re-adjusting to Pasadena time would be a good idea, so stayed up until about 4am surfing the internet, editing videos, writing websites, reading physics, etc.

Next day I got up at about 2pm, ate breakfast, read physics, ate lunch, read physics, and ate dinner at the Indian place again. The food was excellent, but the mathematics in the check/bill was terrifying. Maybe I've just got quantum physics in my brain? I think a currency based on non-commutative representations, or complex numbers, or something stranger still, would be very interesting.

That afternoon, a fellow guest and I had a long question and answer conversation, which ended disappointingly (but unsurprisingly) with him equating cancer and sin as potentially curable yet possibly unknown diseases. I think I landed a hit when I pointed out that actually 1) the ten commandments were explicitly superseded by the gospel of JC, and 2) the ten commandments do not prohibit slavery, amongst other things that should be pretty obvious to people living inthe 21st century. Overall the affair was refreshingly civil, and happily terminated before frustration levels rose!

Next day I got up at 8am, took a cab to the airport with a rather chatty great-grandmother, who had apparently found a new boyfriend a few years before at the age of 81 =D. The auto-check-in at US Airways nearly destroyed my passport, then my patience, but in due course I was in the line for security. The agent, Ashby, was the nicest, funniest TSA agent I've ever seen. Possibly the only one. Orlando international airport has free wifi, so all my material needs were being met.

In the departure lounge, I met a number of zumba instructors, who informed me that in fact there had been a convention that weekend in Orlando, and 6000 people were there! They then proceeded (without prompting!) to give me an account (complete with photos) of some of the outrageous parties they had held over the weekend. The fun I missed out on while sweating on my computer in front of endless iterations of Schrodinger's equation...

I also indulged (privately) in a game evil-me likes to call 'fatty-roulette', in which one looks around the lounge and tries to estimate the odds of having to share half your seat in economy with someone who will probably insist on having the arm rests up, and quite possibly have questionable hygiene too. Ah, the joys of cattle class. More leg room than in coaches, and better seats, but still, at my size, a bit of a squeeze. Flying international I usually can manage an exit row for at least one leg, but in the US you have to pay extra! If it's any consolation, the people in first class always look pretty unhappy and uncomfortable, which has always been a bit of a mystery to me. Fortunately, in both legs of today's travel I was okay! First one I had a chatty, bright and tiny 5 year old, and second leg was a French tourist. When I think of foreign words for something now, I think in Russian. Pushing that to one side, an amorphous soup of Latin, Italian, and French floats to the surface. Simply set the jaw at the correct angle, clear the throat, and hold forth.

At one point I looked forward through the window and saw an awesome and rather exciting row of enormous thunderstorms ahead of us. The bumps were, however, a mere 3/10 before the pilot descended 'for your comfort'. In 2004 I flew Narita to Sydney in July on a 777 and it was spectacularly bumpy. They served breakfast and dinner during the same 10 minute quiet spot, but otherwise moving around the cabin was impossible. The entire plane shuddered up and down, and since I was up the back, side to side too, with a nice wide range of frequencies, interspersed with multiple consecutive periods of freefall. The first two the flight attendant calmly ascended and descended from the ceiling, but on the third she screamed, which is when, I suppose, it was getting interesting. That was probably a 9/10.

West of the storms, the air was spectacularly clear, and though I saw neither the Grand Canyon nor the Sierras from my side of the plane, the graben block faulting is still visible and awesome in that part of the world. Quite reminiscent of the Mongolian Altai. Beautiful rugged dark mountains between flat alluvial pans with confused and jagged drainage patterns.

Soon enough we kissed the tarmac at LAX, I jumped in a shuttle, and was home. The advantage of travelling with only a few shirts stuffed around your laptop is that it took about 2 minutes to unpack! The only casualty of the otherwise highly successful trip was a small container load's worth of astronaut icecream, which is substantially more brittle than I had expected. Same (i.e. nil) nutritional content, however, in powder form.